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Closed mappings and quasimetrics


Author: Jacob Kofner
Journal: Proc. Amer. Math. Soc. 80 (1980), 333-336
MSC: Primary 54E15; Secondary 54C10
DOI: https://doi.org/10.1090/S0002-9939-1980-0577769-6
MathSciNet review: 577769
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Abstract: Closed continuous mappings with first countable images preserve quasi-metric spaces as well as nonarchimedean quasi-metric spaces and $ \gamma $-spaces. This is a strict generalization of analogous results on perfect mappings: there exists a closed continuous mapping of a nonarchimedean quasi-metric Moore space onto a compact metric space which is neither perfect nor boundary compact.


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Additional Information

DOI: https://doi.org/10.1090/S0002-9939-1980-0577769-6
Keywords: Closed mapping, quasi-metric, nonarchimedean quasi-metric, $ \gamma $-space, perfect mapping, first countable space
Article copyright: © Copyright 1980 American Mathematical Society

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